Refrigerating apparatus



Sept 11, 1928.

S. OTTO REFRIGERATING APPARATUS Filed Dec. 5, 1925 4 Sheets-Sheet 2 INVENTOR 4 JZaar/ fil /0 BY 7 WW W A mus Sept. 11, 1928.

5. OTTO REFRIGERATING APPARATUS Filed Dec. 5, 1925 4 Sheets-Sheet 5 Alllllll INVENTOR 1 flat! 0:20

- AM ATTORNEYS I Sept. 11, 1928. 1,684,196

S. OTTO Y REFRIGERATING APPARATUS Filed Dec. 5,. 1923 4 Sheets-Sheet 4 M ATTORNEYS .Patented Sept. 11, 1928.

' 7 UNITED STATES smear marenm'ron conrmy, a

PATENT OFFICE.

one, or scm'ron, munsnvamA} ASSIGNOR r ICELESS nu'ronarrc oonronmrroir or DELAWARE.

' I 'nnrmenanrme arrnnarus.

i Application fled December 192 3." -'Seria1 No. 678,572.

pressure to pass to an upper or distillation chamber, and there retained during distillation. The resulting weak liquor is then cooled or permitted to cool, whereby it returns to the lower orabsorption chamber by the action of gravity and the reduction in pressure in the lower or absorption chamber,

. and remains there during the absorption of the feturning gas delivered below the liquid eve As a further important feature there is provi ded improved heating means so constructed and arranged as to reduce to a minimum the height of the boiler absorber and permit the use of a bottom water jacket.

As a further important feature there is provided improved means whereby the lower or absorption chamber is more effectively cooled duringthe absorption action.

As a further important feature there is provided improved rectifying means for condensing water vapor from the distillation gasesso that only the anhydrous ammonia eaves the boiler absorber.

As a further important feature I have so designed the parts that the minimum number of dies are required in making the parts and the cost is correspondingly reduced.

. Certain of the important features of my invention have for their object to better adapt the apparatus to the small space available on the top of a refrigerator of the shape and size commonly employed for household purposes, and to render it entirely automatic and fool-proof in its operation. Among these important features are means for insuring the lighting of the gas at the burner upon the turning on of the gas, means for automatically shutting off the gas in case the pres sure exceeds a redetermined limit, as for instance upon failure of the cooling water supply, means for permitting escape of gas to sewer when the pressure exceeds a higher predetermined limit, time controlled mechanism for automatically operating the gas and cooling water valves at the'beginning and end of the heating period, and means for ef" fecting the return of liquid from the lower part of the evaporator in case liquids, not

readily volatile at the temperature of the evaporator, accumulate in the latter. In the accompanying drawings:

Fig.1 is a central vertical section through one form of boiler-absorber, certain of the other parts of the apparatus being also shown in section, and certain of the parts ,being shifted from preferred position to facilitate illustration. v

Fig.2 is a transverse sect-ion on the line 2-2 of Fig. 1.

Fig. 3 is a top plan view of a portion of the apparatus. i

Fig. 4 isa side elevation taken on the line 4-4 of'Fig. 3.

Fig. 5 is a diagrammatic illustration of the wiring circuit, and

Figs. 6, 7, 8 and 9 are central vertical sections of four other forms of boiler-absorbers shown somewhat diagrammatically.

The boiler-absorber illustrated in Fig. 1 of the accompanying drawings includes an upper or distillation chamber 10 and a lower or absorption chamber 11 separated by a substantially horizontal partition 12. In order to make the boiler-absorber capable of withstanding higher internal pressure the peripheral wall 13 of the upper chamber may be made integral. with or welded to a domeshaped top 14, and the peripheral wall 15 of the lower chamber may be made integralwith or welded to a cup-shaped bottom 16. The upper chamber is shown of a diameter somewhat greater than that of the lower chamber and the two peripheral walls telescope and are provided with inter-engaging flanges 17 and 18 which may 'be welded together. The partition 12 is welded to the peripheral Wall 15 at the upper end of the latter and preferably at a point where this wall spreads out to form the flange 17.

The lower compartment or chamberll has i no normal refrigerant or liquid'inlet or outlet except'a. pipe 19 which extends from the lower part of the upper chamber, through the partition 12 and terminates in a perforated head closely adjacent to the lower part of the lower chamber. The parts of the boiler-absorber so far described in detail are shown substantially the same as in Fig. 2 of m patent above referred to.

My improved heating means includes an vice 23 and gas shut ofi valve 24.

Encircling the burner is a housing 25 in the form of a cylindrical wall open at the bottom to admit air to the flame. The upper end of this housing may be connected to the peripheral wall 13 of the upper chamber at a point spaced somewhat above the bottom 12 of the upper chamber so that the heat from the burner is applied most efiectively to the upper part of the lower chamber and the lower part of the upper chamber. The products of combustion may escape from the annular space encircled by the housing 25 through any suitable number of fines or chimneys 26.

Withinthe housing and adjacent to the burner is a suitable pilot for lighting the burner when the gas is turned on. In some constructions this may be in the form of an ordinary pilot light but for greater safety I preferably employ electric resistance wire 27 having its terminal lead wires 28 and 29 extending through the housing 25 above the burner. As will be later pointed out the o ening of the main gas valve is accomp ished by the closing of an electric circuit which circuit may include the resistance wire 27, so that as the current is turned on to open the gas valve the resistance wire becomes heated to ignite the gas. This mechanism will be referred to hereinafter in connection with the mechanism for controlling the gas valve.

As in my prior atent above referred to, the heating of the iler-absorber causes the gas pressure in the upper part of the lower chamber to force the strong liquor up through the pipe 19 into the upper compartment where it is heated to effect a distillation action. It will be noted that the heat is applied from the burner by conduction from the wall 15 to the walls 12 and 13, and also by the action of the hot combustion gases directly on the lower part of the wall 13. Li uid remaining in the bottom of the lower c amber continues to vaporize and the hot vapors or gas act on the partition 12 and'also pass up the pipe 19 and bubble through or condense in the liquid in the upper chamber to aid in heating the later.

To effect a rectification of the gases driven off from the strong liquor in the upper compartment I provide acooling coil 30 adjacent to the top or dome 14 of the distilla tion chamber. The gases are caused to come into intimate contact with the cooling surfacesof the coil by means of a pair of perforated bafile plates or partitions 31 and 32, one above the cooling coil and the other below. The lower plate 31 has perforations adjacent to the periphery and the upper plate has perforations at the center so that the gas takes a spiral path between the convolutions and is kept adjacent to the cooling surface of the coils. Further rectification is accomplished by a water jacket 33 formed by a dome or top wall 34 having its peripheral edge welded to the outer edge portion of the top wall 14. Within the water jacket there is provided a rectifier coil 35 of spiral form. This coil has its lower end 36 extending through the wall 14 and communicating with the space above the partition 32, while the opposite end of the pipe extends through the top wall 34 of the water jacket and connects with the main refrigerant gas conduit 37.

It will be noted that the refrigerant gas driven off from the strong liquor during the heating of the still flows through the apertures in the plate 31, between the convolutions. of the coil 30, through the apertures of the plate 32, and then through the coil 35 to the conduit 37. The water vapor which is driven off from the liquor by the heating ac" tion is condensed by the cooling coil 30 and by the water jacket around the rectifier coil 35, so thatthe gas which flows out through the conduit 37 is substantially pure ammonia, if this be used as the refrigerant gas. The rectifying coil of spiral form with a gradual pitch from one end to the other, permits the draining by gravity therefrom of any condcnsate in said coil.

Insome'constructions I may omit the cooling coils 30 and baflies 31, 32, and rely solely on the rectifying coil for separating out the water vapor. I may in some constructions utilize solely the cooling coil and bafiles and omit the upper water jacket and rectifying coil. The amount of cooling surface required will depend in part upon the size of the apparatus, the temperature of the cooling water employed, and the temperature and pressure for which the particular boilerabsorber is designed.

In the lower or absorption chamber I provide a cooling coil 38 which is employed only during the absorption action, when the: heat is shut off. This cooling coil may be of-any suitable character, but is shown as havingits outlet end 39 delivering to a water jacket 40 similar to the upper water jacket 33, except that it is disposed below the bottom Wall 16 of the lower compartment. This water jacket is 9? mal operation of the'apparatus. This pipe jacket being 'provide the coil 38 and the (jacket 40 in series, the with a water outlet 42. This outlet is placed at the upper part of the jacket to prevent air from being tra ped in the jacket, but the jacket is also provided with auxiliary outlet 42 normally closed by a valve. This valve may be opened to drain the jacket when the apparatus is out of commission. This bottom water jacket is important as it serves to insulate the boiler-absorber from the refrigerator box below and prevent radiation of heat to the latter.

In connection with my improved boilerabsorber-I employ a condenser which is preferably in the form of a counter-current coil encircling the upper part. -The inner pipe 43 serves for the cooling water and the outer pipe for the refrigerant gas. The cooling water is delivered from any suitable source of supply through a pipe 45 directly to the inner. pipe 43 of the condenser at the lower end of the latter, and the opposite end of the condenser pipe 43 is connected by a pipe 46 to the water jacket 33. The upper part of the water jacket at the opposite side is connected to the outer end of the upper one of the separator coils 30 by a pipe 47 and the outer end of the lower one of the separator coils is connected to an outlet pipe 48. The inner end of one of the coils 30 is connected to "the inner end of the other so that the two are inseries.

The pipe 48 leads to a three-wayvalve 49 which has one outlet 50 leading to a waste pipe 51 and a second outlet connected to a pipe 52 leading to the absorber cooling coil 38. The outlet pipe 42 from the lower water jacket leads to the waste pipe 51. Thus the water may be continuously delivered through the separator coil 30 and upper water jacket, and may then flow either tothe waste or through the absorber cooling coil and lower water jacket and to the-waste. Means for operating-the three-way Valve 49 will be referred to-hereinafter.

The combustible gas employed for heating the boiler-absorber is delivered through a gas supply pipe 53 to a main valve 54, and thence through a pipe55 to the valve 24 and burner, In this pipe 55 there is provided a safety valve 56 which includes a valve member 57 and an operating diaphragm 58. The diaphragm is clamped at its edges and is of ductile metal. In case the refrigerant gas pressure beneath the diaphragm exceeds a predetermined limit, the diaphragm bowsoutwardly to force thevalve to its seat and shut off the combustible gas, but without rupturing. WVhen the pressure decreases the diaphragm remains bowed and keeps the gas shut olf until the diaphragm is removed and replaced by a new one.

The pipe 37 constitutes the only inlet and outlet to the boiler-absober during the nor leads to a three-way valve 59 from which a pipe 60 leads to the upper end of the outer coil 44 of the condenser. The opposite lower end of the condenser pipe 44 is connected by a pipe 61 to the upper part of the evaporator which is located'in the refrigerator or other compartment to be cooled, and which is not illustrated as it forms no portion of the present invention. The three-way valve 59 is also connected to a pressure gauge" or venting pipe 59 and to a pipe 62 leading to the lower part of the evaporator.

In normal operation the three-way valve 59 is set to permit free flow of gas therethrough from thepipe 37 to the pipe 60 or in the reverse direction, and to communicate with the pipe 59* which is closed at the outer end. In case water or weak liquor accumulates in. the lower part of the evaporator the i valve 59 may be turned to connect the pipe 62 with the pipe 37 and" close the pipe 60. The closing of the pipe 60 will prevent any return of gas from theupper part of the evaporator through the pipe 61 and condenser, and the pressure developed in the evaporator by theevaporation of the liquefied ammonia or other refrigerant gas will force liquid fromthe lower part of the evaporator upthe pipe ter or weak liquor is distilled over into the evaporator. .For shipment the valve is turned to close pipe 3! so as to shut oil all communication between the boiler-absorber and the evaporator, and preventliquid from 1 passing to the evaporator should the case be tipped over;

In case there 1s any failure of cooling water or'if for any other reason press'ure'should develop in the system far 1n excess of the normal I operating pressures and which might cause danger ofexploslon or rupture of any oftheparts or oints, this pressure may be relieved through suitable safety apparatus. The upper part of the boiler-absorber is shown as connected by a pipe 63 to a normally open shut-off valve 64 and a normally closed'relief valve 65. This relief valve is provided with a spring 66 which may be adjusted by a movable abutment 67 so as to resist all normal pressures in the system. For instance the spring may be set to open in case the pressure in the system reaches 300 pounds. The outlet side of the relief valve is connected by a pipe 68 to the diaphragm 58 of the gas valve 57 so that in case the pressure'in the system reaches the predetermined limit of 300 pounds, refrigerant gas may bow the diaphragm 58 and shut off the heating gas to prevent further heating of the boiler-absorber. The outlet side of the relief valve is also connected by a pipe 69 to the waste water discharge pipe 51, and in this pipe there is arranged a diaphragm 7 0 of ductile metal clamped at the periphery. The casing beyond the diaphragm permitsthe latter to bow and to rupture in case the pressure reaches a predetermined limit. For instance the diaphragm 70 may be of such material that it will rupture at 460 pounds pressure, so that the excess pressure will be relieved and the excess gas permitted to escape through the waste water pipe to the sewer. In case the gas pressure should rise to above 300 pounds but less than 460, the relief valve 65 will openand the gas valve 57'closes without loss of refrigerant. As the heat is dissipated, the pressure drops but the bowed or expanded disk 58 holds the gas valve 57 closed and prevents the turning on of the gas when there is no pilot light to reignite it. The disk must be renewed be fore it can operate again.-

In the operation of the apparatus the gas valve 54 and the three-way water valve 49 are operatedsimultaneouslysothatwateristurned on to the absorber cooling coil 38 and lower water jacket when the heating, action is shut off, and water to this coil and jacket is shut oif when the heating gas is again turned on. These valves are operated by an electric motor and the motor is preferably controlled by clockwork so that the distilling operation and the absorbing operation are continuous for predetermined time intervals, These intervals may be determined in accordance with the size and proportion'of the parts and the refrigerating action required for the cooling of the evaporator.

In practice two complete cycles in twentyfour hours f has proved very satisfactory. The distillation operation may continue for one hour during which the heat is turned on and the ammonia i gasified or driven off from the strong liquor in the distillation chamber, liquefied in" the condenser, and collected in the evaporator. The gas flows pastthe bafliesBLand 32 and cooling coil 30, then through the rectifying coil 35, pipe 37, valve 59, pipe 60, condenser pipe 44 and pipe 61.

The cooling water flows from pipe 45 through condenser pipe 43, jacket 33, coils 30 and pipe 48 t o valve 49, and to waste pipe 50. During the next eleven hours the heat is shut off and cooling water from the pipe 48 is diverted at I the valve 59 so as to flow through the absorber cooling coil 38 and lower water jacket. The

liquefied ammonia in the evaporator slowly vaporizes and returns through the same cir cuit to the upper chamber 10, and then through the pipe 19 and perforated head 20 into the weak liquor which is now in the lower chamber 11. By returning the gas from the evaporator through the condenser, the condenser water is cooled, but this coolingeflect is not lost as the cooler water goes to the absorber coil 38.

The valves 49 and 54 are operated by an electric motor 71 which has on its shaft a worm 72 for operating a worm gear 72. The

to an arm 77 which is connected to the valve stems of the two valves 49 and 54. The shaft 79 is also connected to the handle or shaft 80- of a snap switch 81.

A clock 82 may have a twenty-four hour 'dial with one pair of contacts spaced twelve hours apart, for instance on hours 12 and 24, and a second pair of contacts also spaced twelve hours apart but one hour beyond the first mentioned contacts, for instance on hours 13 and 1. The electric circuit is such that. the clock turns on the currentforthe motor 71 for each contact of the clock but a snap switch 81 breaks the circuit after the motor has turned the shaft 79 through onehalf a revolution. The snap switch has its contacts so arranged that when the switch is operated it breaks the circuit from one clock contact and closes it for the next successive clock contact. 7 I

The operation is as follows \Vhen the clock closes the circuit at one contact, for instance at hour 24, the circuit will be closed through the motor and snap switch, and the motor will operate to .turn the shaft 79 through one half a revolution and open the gas valve 54 and shift the water valve 49. At the end of this half revolution which takes only a few seconds the snap switch breaks this circuitbut establishes new connections to the next contact on theclock, namely that at the hour 1. The motor stops through the breaking of the circuit at the snap switch and the heating operation continues for the predetermined time period, namely one hour. At the end of the hour the clock closes, the circuit at the 1 hour contact which is in series with closed contacts of the snap switch, and the motor is again operated to rotate the shaft 79 through another half revolution to shut off the gas, shift the water valve, and break shifts-the gas and water valves and then cuts its own circuit.

I have not illustrated the details of the snap switch as such forms no portion of the present invention and such switches are Well known. It will be understood that in the .present' instance the contact making and breaking blade or other member of the switch remains stationary during the rotation of the shaft 79 through substantially and that said blade or member then suddenly jumps forward 180 to thenext position through the action of a suitable spring, thus opening one branch and closing the other.

As one important feature of my invention the electric circuit includes the resistance wire 27 which acts as a pilot for the burner. Preferably the resistance is in the branch circuit which is closed to start the motor and turn on the gas, and is not in the branch operating to start the motor and shut off the gas. In the present instance it is in the circuit of the 12 hour and 24 hour contacts. The motor cannot start at thesetimes to turn on the gas except upon a flow of current through this resistance wire, and such flow of current heats the resistance wire to incandescence. Therefore the gas can never be-turned on except when the pilot light is in condition for igniting the gas. In case the electric supply circuit should be broken or temporarily shut off, the motor cannot turn on the gas. There is no waste of heat in maintaining the pilot light as it is not in operation except at the particular periods of a few seconds each during which. the motor is being operated to tur on the gas. This feature'of my present invention is capable of use in various other systems where a gas burner valve is to be opened and closed. For instance, in a gas heated hot water heating system the gas valve may be operated by a motor having a resistance wire pilot for the gas flame in circuit with the motor. The circuit may be opened and closed by any form of switch operated in any suitable manner as for instance by thermostat or clock work.

Anyt-such system including a rotary electric motor for operating a valve would also preferably include a snap switch for stopping the motor as soon as it has accomplished its work. If the motor'be in the form of an electromagnet for opening the valve,'the snap switch is not required.

The flow of water in a hot water heating system may actuate the switch to turn on the current for the pilot and to also actuate the gas valve. In such a construction it is desirable that means be provided for preventing the fiow of water from opening the gas valve if there isno current to heat the pilot resistance. The construction may be made fool-proof by arranging a magnet so that the armature or other moving part thereof controls" the operative connections between the water actuated member and the gas valve. For instance during the first part of the move;

ment of the water actuatedmember it may close the switch of the pilot which is'in the same circuit with an electro-magnet. energizing of the magnet will permit the further movement of the water actuating member to open the gas valve, as by pulling out a stop. If there is no current for the pilot the magnet will not be operated and the flow of water cannot operate to open the gas valve.

The gasvalve 54 constitutes the controlling means for the heating medium. In some cases it may be preferableto use electric heat.-

The,

ing means instead of the gas burner, and in such an arrangement the valve 54 might be snap switch to stop it. In some cases the.

clock might be omitted and a thermostat, float or other device employed for starting the motor, although the same snap switch would preferably be employed for stopping it.

As previously noted the parts preferably would notoccupy the same relative positions as illustrated in'Fig. 1, this view showing them rearranged so far as the relative locations are concerned in order to facilitate clear disclosure of the essential features and the method of operation. The parts are preferably so positioned in respect to each other as to facilitate the placing of them within the area represented by the top of an ordinary refrigerator, so that access can "be gained to the various parts that may need attention. In Fig. 1 certain minor details which might be desirable in a commercial installation have not been illustrated as they form no portion of my invention, such for instance as insulation around the housing 25 and the upper.

art of the boiler-absorber. I have shown the chamber 11. This is provided with a sealed closure 84 and serves for the initial filling of the apparatus with water and refrigerant gas, and also permits of the venting from the system of air or other gases not liquefiable at the normal pressures and temperatures of the apparatus. I have also shown the peripheral wall of the absorption chamber provided with a projecting band 85 against which the flame may pla and which protects the wall of the boiler-a sorber from the direct action of the flame.

It will be apparent that many of the features of my improved construction, particularly those relating to the electric motor actuating parts, the pilot, the safety control ofpressure, etc., may be employed in connection with any of the specific forms of boiler -ab-.

sorbers shown in my prior Patent 1,470,638,

or other specific constructions as for instance construction illustrated the outlet pipe 37' from the upper part of the distillation chamber 10, leads to the lower part of a jacket 88 which, is below the absorption chamber 11. The upper or distillation chamber has a jacket or casing 25 in the lower part of which is a burner 21. The condenser encircles the lower portion of the apparatus and has an inner pipe 13 connected in series with coils 30 in the separation chamber 88. The outer pipe 4.4 of the condenser has one end connected to the upper part of the separation chamber and the opposite end to the evaporator. Any water which may be distilled off during the heating period and pass down the pipe 37, will be condensed in the chamber 88 and remain there while the gas goes on to the condenser. During the absorption period any liquid which has collected in the chamber 88 will be sucked up through the pipe 37 and returned to the absorption chamber as the only ports at the lower end of the pipe 37 are closely adjacent to the lowermost part of the jacket 88. I

In Fig. 7 I have shown a construction very similar in many respects to that shown in Fig. 1, exceptthat the parts areso designed as to permit-manufacture at the lowest possible cost. The top jacket wall 34, the top wall 14* of the distillation chamber, the partition 12", the bottom wall 16 and the bottom jacket 4:1 are all made of exactly the same diameter and the same curvature so that they may be produced by a single pair of dies. The parts vary only in the length of the peripheral wall. The top jacket 34 and top wall 14 may have the same length of peripheral wall, and may thus be stamped out identically the same. The bottom jacket etl preferably has a shorter peripheral wall. The peripheral wall 13 which is integral with the partition 12 may be welded to the peripheral wall of the top l l 'at a seam 89. The peripheral wall 15 of the absorption chamber and which is integral with the bottom wall 16 may be welded at a seam 90. The two jackets will be welded at the seams 91 and 92. The cooling coil 38 which is shown in the absorption chamber is of conical form with the lower end connecting to the lowermost point of the bottom water jacket.

In the upper water jacket the coil may include two conical sections 35 and 44* in superposed relationship, the lower coil 35* serving as a rectifying coil and having its lower outer end communicating with the distillation chamber. The upper coil 44 may serve as a condensing coil and have its upper inner end connected to the upper inner end of the lower coil. I

In Fig. 8 I have shown somewhat diagrammatically a construction of absorption chamber which may be employed in the forms K shown in Figs. 1, 6 and 7 if desired. In this arrangement the absorption chamber is divided into two compartments 11 and 11" in superposed relationship, and separated by a partition 93. A pipe 19 leads through the partition 12 from the distillation chamber 10 to a point near the bottom of the chamber 11. That is, near the artition 93. A second pipe 19 leads throng from the distillation chamber through both of the partitions 12" and 93 to a point adjacent to the bottom of the lower absorption chamber 11. By means of this arrangement I am able to get a lower evaporation pressure in the evaporator, as there is less head of liquor in the absorber through which the gas must pass. For instance, if the apparatus shown in Fig. 1 be of such size that the liquid level at the end of the absorption period is eight inches above the outlet of the pipe 19 the lowest portion of the gas can reach the liquid only by overcoming this head of eight inches of liquor. With the arrangement shown in -Fi 8 the same volume of liquor would be divi ed into two chambers, and there would be a head of only four inches of liquor in the chamber 11' above the lower end of the ipe 19, and a head of only four inches in the chamber 11 above the lower end of the pipe 19. This permits a lower evaporation ressure in the evaporator and a more comp ete utilization of the liquefied gas. It will be apparent that during the heating period liquid from both chambers 11 and 11" is delivered up through their respective connections to the distillation chamber.

In the construction shown in Fig. 9 I have illustrated certain further features of importance. The upper water jacket 33 which serves to house a rectif ing coil 35 and a. condensing coil44, as in ig. 7, also has a dome shaped portion 94 with a water outlet 48 provided with a valve 49 This outlet pipe is below the u rmost portion of the dome,

anda pipe 95 eads from this n permost portion to the'water jacket 40 w 'ch is below the absorption chamber. This pipe may extend directly through the distillation rise to a higher level in the dome 94 and flow through the pipe 95 and the water jacket 40. The gas in returning through the dis-- tillation chamber to the absorption chamber through the pipe 19 would thus flow along,

the water cooled pipe and reach the liquor at the bottom of the pipe 19 at a low temperature. This arrangement avoids the necessity of a separate cooling coil in the absorber. The suppl of water may enter by a pipe 45 andthen [lbw through a jacket 96 to the jacket 33". The jacket 96 encircles the pipe 61 which leads from the upper part of the evaporator to the condenser coil 44. The return suction pipe 62 leading from the lower part of the evaporator may also pass through the jacket 96 and enter directly lnto the upper part of the distillation chamber.

7 As a heating means I have shown not only an annular burner 21 but heater tubes 97 and 98, one in thedistillation chamber and the other in the absorption chamber, and receiving electric heating units, as set forth in my prior patent above referred'to.

It will of course be understood that various features of the different forms disclosed in Figs. 1, 6, 7, Sand-9 may be utilized in a single construction, and in various different combinations and arrangements.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. A boiler-absorber for refrigerating apparatus including a vessel having a dome shaped top wall, a water jacket for cooling the upper surface of said wall, and a gas rectifying coil of spiral form within said water jacket, the outer lower end of said coil communicating with the interior of said vessel through said top wall at a point adjacent to the periphery of the latter and the upper endof the coil extending through the outer wall of the water jacket, whereb during heating liquid condensed from t e gas passing through said coil may drain back into said vessel, and means for delivering gas to the lower part ofthe vessel during the cooling period.

2. A boiler-absorber for refrigerating aparatus including a vessel having a water jacket for cooling the top wall thereof, a separate water jacket for cooling the bottom wall, an annular heater encircling the vessel intermediate of the upper and lower ends thereof, means for delivering cooling water through said jackets in series and means for deliveringrefrigerant gas to the lower part of the vessel duringcooling and permitting escape of gas from the upper part of the vessel during heating.

3. A boiler-absorber for refrigerating apparatus including a vessel having a water jacket for cooling the top wall thereof, a separate water jacket for cooling the bottom wall, means for delivering cooling water through said jackets in series, said means permitting the delivery of water through one of said jackets independently of the other and means for delivering refrigerant gas to the lower part of the vessel during cooling and permitting eacape of gas from the upper part of the vessel during heating.

4. A boiler absorber for refrigerating apparatus including a vessel having an upper distillation chamber, a lower absorption chamber, communiction means from the lower port of one chamber to the lower part of the other, a water jacket for cooling the top wall of the upper chamber, and a separate 'water jacket for cooling the bottom wall of the lower chamber.

5. A boiler-absorber for refrigerating apparatus including a vessel having an upper distillation chamber, a lower absorption chamber, communication means from the lower part of one chamber to the lower part of the other, a water jacket for cooling the.

top wall of the up er chamber, a separate water jacket for coolmg the bottom fall of the lower chamber, means for delivering water continuously throu h the upper water jacket. and intermittently through the lower water jacket.

6. A boiler-absorber including a vesselhaving a chamber adapted to serve as an absorber, a cooling coil within said chamber, a Water jacket for cooling the bottom of said chamber, said cooling coil and said jacket being connected in series and means for delivering refrigerant gas to the lowerpart of the vessel during cooling and permitting escape of gas from the upper part of the vessel during heating.

7. A boiler-absorber including avessel having a chamber adapted to serve as an absorber, a cooling coil withinsaid chamber, a water jacket for cooling the bottom of said chamber, said cooling coil and said jacket being connected in series, and an annular heater encircling said chamber above said water jacket.

8. A boiler-absorber for refrigerating apparatus including a vessel'having an upper distillation chamber, a lower absorption chamber, andm'eans establishing communication between the lower part of one chamber and the lower part of the other, said upper chamber being of larger diameter than said lower chamber, and said lower chamber having an annular heater encircling the same above the bottom thereof of smaller internal diameter than said upper chamber and directly below the latter.

9. A boiler-absorber including a vessel having a partition subdividing the same into an upper distillation chamber and a lower absorption chamber, gas inlet and outlet means from the upper chamber, communication means between the lower part of the lower chamber and the lower part of the upper chamber, and an annular heater encircling the vessel.

having a partition subdividing the same into an upper distillation chamber and a lower absorption chamber, gas inlet and outlet means from the upper chamber, communica- 10. A boiler-absorber including a vessel tion' means between the-lower part of the lower chamber andathe lower part of the upper chamber, an annular burner encircling the lower chamber below said. partition, a casing encircling said burner and lower chamber, and a flue extending from the upper part of said'casing toa point above said vessel. v

11. A boiler-absorber including a partition subdividing the same into an upper distillation chamber and a lower absorption chamber, gas inlet and outlet means from the upper chamber, communication means between the lowerpart of one chamber and the lower part of the other, and a combined filling and foul gas outlet conduit leading from the upper part of the lower chamber, and means normally sealing said conduit.

12; A refrigerating apparatus including a boiler-absorber, a burner for heating the same, a gas valve for the burner, a rotary electric motor for opening and closing said gas valve, switch mechanism for controlling said motor, means for closing said switch mechanism to start the motor at predetermined time intervals, means operated by the motor for stopping the latter when thevalve has moved from open to closed position, or vice versa, means for cooling the boiler absorber,'means for permitting escape of gas from the upper part thereof during heating operation, and means for delivering gas to the lower part during cooling operation. 7

13. A refrigerating apparatus. including a boiler-absorber, a heater. a controlling means for the supply of heating medium to said heater, an ei'nergency outlet conduit leading from said boiler-absorber, a rupture disk in said conduit for permitting escape of refrigerant gas through said conduit when the pressure exceeds a predetermined pressure, and means operable to close said controlling means when the gas pressure in said conduit in advance of said rupture disk reaches a second, but lower predetermined limit.

14. A refrigerating apparatus, including aboiler-absorber, a heater, means for cooling the boiler-absorber, means for permitting the escape of gas from the upper part thereof during heating operation, means for delivering gas to the lower part during cooling operation, automatic means for controlling the supply of heating medium to said heater, independent emergency means for shutting oh the supply of heating medium to said heater, a conduit for the emergency escape of gas from said boiler-absorber, a rupture disk in said conduit for permitting such escape when the pressure ezgcecds a predetermined limit, and a diaphragm communicating with said conduit in advance of said disk and operating to close said emergency means when the pressure reaches a second, but lower predetermined limit.

15. A refrigerating apparatus, including a boiler-absorber, heating means therefor, cooling means therefor, means for permitting the escape of gas from the upper part thereof during heating operation, means for delivering gas to the lower part during coolingoporation, a conduit for supplying heating medium to said heater, time control'means for controlling the supply of heating medium through said conduit, independent controlling means for controlling the supply of heating medium through said conduit, means for automatically operating said second mentioned means when the pressure in the boilerabsorher exceeds a predetermined limit, and an outlet conduit leading from said boilerabsorber and having a rupture disk permitting the escape of gas from said boiler-absorber when the pressure exceeds a higher predetermined limit.

Signed at New York in the county of New 0 York and State of New Yorkthis 24th day October, A. D. 1923. I

STUART oT'ro- 

